Stencil sheet



phous prepared by coating the such as Japanese yoshino- Patented Nov. 2, 1937 UNIT STATES PATENT OFFICE 'n-JIZ'LLH it I Shiniiro Horii, Kanda-kn, Tokyo, Japan No Drawing.

Application May 7; ho. 141,248. In Japan Marsh 1937, Serial 31, 1937 2 mm. (01. n-sas) This invention relates to improvements in tencil sheets for use in duplicating manuscript or typewritten documents, drawings and the like, consisting of a sheet of fibrous material provided with a coating which is impermeable to ink and may be cut through by the type of a writing machine or by a stylus.

Heretofore it has been proposed to prepare a stencil sheet consisting of a porous base, such as yoshino paper, coated with a material including a gelatinous organic colloid. dispersed in an aqueous medium, an oily softening agent and an inorganic body capable of forming colloid sols in the disperse medium ing out of the oily softening agent.

Ithas also been proposed to prepare a stencil sheet provided with a coating of coagulated or non-coagulated gelatine, having homogeneously dispersed therethrough an oily softening agent and an organic filler, such as beechwood flour, which prevent sweating out of its ingredients.

In the present invention the stencil sheets are sheets of a fibrous base. paper, with a coating material comprising a gelatinous organic colloid, such as gelatine, dispersed in water, an oily softening agent and diatomaceous earth.

Diatomaceous earth is essentially an amor-.

silica of organic origin, being the fossil remains of microscopic plants known as diatoms. This material is an impalpable powder of extreme lightness, high absorptive capacity and high silica content. It mixes and bonds well withthe material' containing proteins and oily softening agents, and. consequently, it tends to maintain the homogeneity of the coating, togive the excellent finish of increased hardness and flexibility and to improve the cutting quality of the coated sheet.

In carrying out the invention a gelatine of high jelly strength is swelled by soaking in water and is disaolvedin hot water. The solution is then mixed and emuisinedgwith Turkey-red oil and othersuitable oilyl ftening agents, suchas and which prevent sweatthe coating fatty oil, fatty acid esters, mineral oils, oleic acid, oleyl alcohol and diatomaceous earth, in admixture with dyes or pigments. To the composition there is added a small amount of a suitable solvent, such as cyclohexanol, a hardening agent, 5 such as formalin or hexamethylenetetramine, and a preserving agent, such as phenols or their derivatives.

The proportions of the ingredients of the composition may vary according to several oircumstances. The following is an example:-

Parts by weight Gelatine 10 Oleic acid monoor di-glyceride 5 Glycol oleate 5 Oleyl alcohol 5 Heavy mineral oil 1 5 Turkey-red oil 15 Ultramarine blue l0 Diatomaceous earth 20 Water I h 300 Cyclohexanol 5 Hexamethylenetetramin 1 ,Preservative 1 The basic 'yoshino paper may be coated with material above'described in any desired manner.

What I claim is:-

l. A stencil sheet consisting of a base of fibrous material coated with a coating material comprising gelatine, oleic acid mono-glyceride, glycol oleate, oleyl alcohol, a heavy mineral oil, Turkey red oil, ultramarine blue. diatomaceous earth, water, cyclohexanol, hexamethylenetetramine and a preservhtive.

2. A stencil sheet consisting of a base of fibrous material coated with a coating material comprising gelatine, oleic acid di-glycerid'e, glycol oleate. oleylalcohol, a hea mineral oil, Turkey-red oil, 40

preservative. t Y 

